<chapter>
  <title>Data Model</title>
  <section>
    <title>Syntax For Data Model</title>
  </section>
  <section>
    <title>XML</title>
    <section>
      <title>Basic Syntax</title>
    </section>
    <section>
      <title>XML and Semistructured Data</title>
    </section>
  </section>
</chapter>

